Many vehicles include one or more headlamps (also referred to as headlights) usually attached to the front of the vehicle. Headlamps usually have the purpose of illuminating the road ahead during periods of low visibility, such as darkness or precipitation, but also serve to alert or signal the location of the vehicle to other vehicles and pedestrians.
When two or more vehicles approach each other, their respective headlamps may cause glare to the driver of the opposing vehicle. Headlamps are often configured to operate with more than one level of brightness or intensity, often referred to as low beams and high beams. Operation of the vehicle with high beams may increase glare to the driver of the oncoming vehicle.
Other sources of light may also cause glare to the driver of the vehicle. For example, and without limitation, road-side signage may incorporate bright lights projecting onto the roadway, spot lights may be used for numerous purposes on or near roadways, or the sun may be positioned in the view of drivers—especially during early morning or late afternoon driving.